<?php

/*
 * This file is part of SwiftMailer. (c) 2004-2009 Chris Corbyn For the full copyright and license information, please view the LICENSE file that was distributed with this source code.
 */

/**
 * Reduces network flooding when sending large amounts of mail.
 * 
 * @package Swift
 * @subpackage Plugins
 * @author Chris Corbyn
 */
class Swift_Plugins_BandwidthMonitorPlugin implements Swift_Events_SendListener, Swift_Events_CommandListener, Swift_Events_ResponseListener, Swift_InputByteStream {
	/**
	 * The outgoing traffic counter.
	 * 
	 * @var int
	 * @access private
	 */
	private $_out = 0;
	
	/**
	 * The incoming traffic counter.
	 * 
	 * @var int
	 * @access private
	 */
	private $_in = 0;
	
	/**
	 * Bound byte streams
	 */
	private $_mirrors = array ();
	
	/**
	 * Not used.
	 */
	public function beforeSendPerformed(Swift_Events_SendEvent $evt) {
	}
	
	/**
	 * Invoked immediately after the Message is sent.
	 * 
	 * @param Swift_Events_SendEvent $evt        	
	 */
	public function sendPerformed(Swift_Events_SendEvent $evt) {
		$message = $evt->getMessage ();
		$message->toByteStream ( $this );
	}
	
	/**
	 * Invoked immediately following a command being sent.
	 * 
	 * @param Swift_Events_ResponseEvent $evt        	
	 */
	public function commandSent(Swift_Events_CommandEvent $evt) {
		$command = $evt->getCommand ();
		$this->_out += strlen ( $command );
	}
	
	/**
	 * Invoked immediately following a response coming back.
	 * 
	 * @param Swift_Events_ResponseEvent $evt        	
	 */
	public function responseReceived(Swift_Events_ResponseEvent $evt) {
		$response = $evt->getResponse ();
		$this->_in += strlen ( $response );
	}
	
	/**
	 * Called when a message is sent so that the outgoing counter can be increased.
	 * 
	 * @param string $bytes        	
	 */
	public function write($bytes) {
		$this->_out += strlen ( $bytes );
		foreach ( $this->_mirrors as $stream ) {
			$stream->write ( $bytes );
		}
	}
	
	/**
	 * Not used.
	 */
	public function commit() {
	}
	
	/**
	 * Attach $is to this stream.
	 * The stream acts as an observer, receiving all data that is written.
	 * All {@link write()} and {@link flushBuffers()} operations will be mirrored.
	 *
	 * @param Swift_InputByteStream $is        	
	 */
	public function bind(Swift_InputByteStream $is) {
		$this->_mirrors [] = $is;
	}
	
	/**
	 * Remove an already bound stream.
	 * If $is is not bound, no errors will be raised.
	 * If the stream currently has any buffered data it will be written to $is
	 * before unbinding occurs.
	 *
	 * @param Swift_InputByteStream $is        	
	 */
	public function unbind(Swift_InputByteStream $is) {
		foreach ( $this->_mirrors as $k => $stream ) {
			if ($is === $stream) {
				unset ( $this->_mirrors [$k] );
			}
		}
	}
	
	/**
	 * Not used.
	 */
	public function flushBuffers() {
		foreach ( $this->_mirrors as $stream ) {
			$stream->flushBuffers ();
		}
	}
	
	/**
	 * Get the total number of bytes sent to the server.
	 * 
	 * @return int
	 */
	public function getBytesOut() {
		return $this->_out;
	}
	
	/**
	 * Get the total number of bytes received from the server.
	 * 
	 * @return int
	 */
	public function getBytesIn() {
		return $this->_in;
	}
	
	/**
	 * Reset the internal counters to zero.
	 */
	public function reset() {
		$this->_out = 0;
		$this->_in = 0;
	}
}
